Spool



Och 1943- G. D. ATWOOD 2,331,954

SPOOL Filed July 17, 1940 INVENTOR- Patented Oct. 19, 1943 arissa SPOOLGeorge D. Atwood, Brooklyn, N. Y., assignor to Decorated MetalManufacturing Company, Inc., Brooklyn, N. Y., a corporation of New YorkApplication July 17, 1940, Serial No. 345,887

1 Claim.

This invention relates to spools, and more particularly to textilespools.

It is an object of the invention to provide improved reinforcing meansin a spool of the character indicated.

Further objects of the invention are to provide reinforcing means notrequiring reconstruction of other elements of the spool and permittingthe use of relatively light and inexpensive mate-" rials, such asstamped metal and pasteboard.

The field of use of light-weight, inexpensive spools has hitherto beenlimited by considerations of strength of the barrel to certain types offibers. As a general thing, the finer the thread and the smoother itssurface the greater the pressure produced on the spool barrel will be.

This pressure manifests itself by a flowing of the mass of threadnearest the barrel and the building up of pressure at points along thebarrel not predictable in advance, so that a barrel may fail near' itsends as well as near its center. With fibers such as glas or artificialsilk, the pressure conditions are often so severe as to prohibit the useof conventional pasteboard or metal barrel spools and to require the useof fiber or wooden barrels with attendant expense in spool costs andshipping costs. It is an object of the present invention to extend thefield of 'use of the pasteboard and stamped metal spools into thesefields in which the requirements have hitherto been found too severe topermit their use.

With these and other objects which will appear in the following fulldescription in mind, the invention consists in thecombinations andarrangements of parts and details of construction which will now bedescribed in connection with the accompanying drawing and then pointedout more particularly in the appended claim.

In the drawing:

Fig. 1 is a side elevation of a spool embodying the invention in apreferred form and with the parts progressively broken away to exhibittheir construction in central Vertical section;

Fig. 2 is a plan view of the end of the spool of Fig. 1;

Fig. 3 is a cross section taken on the line 33 of Fig. 1; c

Fig. 4 is a longitudinal central section of the barrel of the spool ofFig. 1 prior to assembly;

and

Fig. 5 is a View similar to Fig. 4 but illustrating the invention in amodified form.

Referring to Figs. 1 and 2, it will be observed that the invention isillustrated as applied to an anti-thread trapping spool constructed inaccordance with Patent No. 2,250,563, granted July 29, 1941, to RawsonAtwood,'and is shown as applied to a spool with stamped metal ends and apasteboard barrel. The spool, generally, includes a barrel I preferablymade of pasteboard or similar material formed of laminated or comminutedsubstances, bonded together with adhesive, or of suitable plastic. Ends2 made of stamped sheet steel or the like are provided and may besurfaced with an anti-thread trapping lining 3 which is rolled into thebarrel l as at 4. The barrel l is fitted into an annular groove 5 formedon each end 2 and is compressed to a certain extent within this groove.The practical limitations on the stamping of metal shapes of thischaracter and the compression of pasteboard or similar materials place alimit upon the thickness of the barrel such that it is not practical tomake the barrel of any desired thickness or of any required strength andit is found in practice that in certain uses reinforcement of the barrelis essential. This characteristic is not peculiar to the pasteboardbarrel spool butis shared by lightweight inexpensive spools with barrelsmade of other materials, it being generally true that the practicalrequirements of the metal stamping and turning art place very definitelimits upon the thickness and strength of the barrel. The ends are heldtogether against the barrel by means of a central eyelet or rivet Binthe customary way.

The spool as thus far described is disclosed fully in theabove-mentioned patent and may be taken as an illustration of one typeof spool to which the invention is applicable. Such spools have beenmade in the past either without reinforcement for the barrel or, asillustrated in the said application, with metal reinforcing elements inthe form of flanged annular discs or rings inside the barrel. I havediscovered that such reinforcements may be dispensed with and a barrelof greater strength and reliability produced by employing as areinforcing member atube i of pasteboard, or the like, positioned withinthe barrel l and preferably having a driving fit thereover the entireouter surface of the tube. In par- 7 ticular, pasteboard tubing usuallyhas a slightly nonuniform diameter, due to the ending of the I outer lapof spirallyewound paper of which it is a composed; and the inner surfaceof the barrel I, when made of pasteboard, will present a similarirregularity,

The reinforcing tube 1 may be made short enough to provide clearancebetween its ends and the spool ends as shown, so as not to introduce anycomplication into the assembly of the spool and requiring inmanufacture, as compared with a nonreinforced spool, merely thesubstitution of a barrel and reinforcement assembly, as shown in Fig. 4,for an unreinforced barrel as one element to be assembled.

As a theoretical matter, it might be supposed that the pressure of thethread against the spool barrel would have the greatest tendency todeform or collapse the latter near its center, and accordinglyreinforcements spaced symmetrically about the center, or approximatelyso, have been employed. In fact, however, the point of collapse may belocated at any point along the barrel length and the reinforcement ofthe present invention provides support at whatever point it is neededand in addition makes available the strength of the pasteboard tube atadjacent points along its length for supporting the outer barrel at thepoint where support is required.

One desirable feature of the present invention is that it is possible toreinforce spools of given design as required for a particular use,omitting the reinforcement to saveshipping weight, when none is needed,and adding reinforcement as required. If greater strength than thatprovided by a single reinforcing tube is needed, it may readily beprovided by positioning within the reinforcing tube 1 one or moreadditional reinforcing tubes 8, as shown in Fig. 5, the spoolconstruction used with the doubly reinforced barrel of Fig. 5 being thesame as that shown in Figs. 1 to 3. In this case the barrel l andreinforcing tubes 1 and 8 may be of successivelydecreasing length sothat the total thickness of the barrel, together wtih itsreinforcements, corresponds approximately at any given point along thespool length to the bending 0r collapsing moment, on the assumption ofuniform thread pressure against the barrel. This feature is i1-lustrated in Fig. 5 in which the broken are C represents the momentalong the barrel, its distance radially from the barrel surface beingproportional thereto at each point along the barrel. As will beobserved, it is possible with the construction of the inventionemploying a plurality of reinforcing tubes to approximate the thicknessof the composite structure step fashion quite closely to the curve.

What is claimed is:

Ina textile spool, and in combination, a tubular barrel of pasteboarol,ends fastened to the said barrel and a plurality of separate tubularreinforcing tubes within the said barrel, the said reinforcing tubesbeing successively shorter and proportioned so that the total thicknessof the barrel and reinforcing tubes at any point along the barrel issubstantially proportional to the collapsing moment at the said point.

GEORGE D. ATWOOD.

